1. Field of the Invention
The present invention concerns a bidirectionally blockable piston-cylinder unit which includes a throttle arrangement to control fluid flow therethrough so as to minimize noise upon switching between opened and closed positions.
2. The Prior Art
A positional piston-cylinder unit to lock movable objects in relative positions to each other is known from DE 4,326,968 A1. Such positional locks are used, among others, in the case of vehicle doors or lids, which on the one hand, should be easily manipulated, but, on the other hand, should also safely carry the respective load. One of the advantages of a piston-cylinder lock according to DE 4,326,968 A1 is that it is possible to make the retaining function independent of the stroke. Other types of units allow the retaining function to occur only within a specific opening range of the vehicle door or lid, or else only in predetermined fixed resting steps.
One of the problems of a unit capable of being blocked in infinite steps is the noticeable switching noise. This type of noise did not occur in the case of earlier, defined blocking position types of piston-cylinder units, and is detrimental to comfort.